1. Field of the Invention
The present invention relates to a printer capable of cutting margins. More particularly, the present invention relates to a printer in which a front margin, a rear margin and side margins can be cut away from an image recording region in a print, and in which a space for containing a blade shifting mechanism is saved.
2. Description Related to the Prior Art
A color thermal printer includes one thermal head. A thermosensitive recording sheet is fed in forward and backward directions, while the thermal head records three-color images according to the three-color frame-sequential recording.
The thermal printer includes a feeder constituted by a capstan roller and pinch roller. The feeder nips the recording sheet and rotates to feed the recording sheet in forward and backward directions. While the recording sheet is fed in either of the directions, a thermal head thermally records the image of a particular one of the colors to the recording sheet. To stabilize the thermal recording, an image recording region is defined in the recording sheet with a size smaller than the periphery of the recording sheet for recording of the image. There are margins created about the image recording region. In the field of silver halide photography, it is usual that a print does not have the margins, and that the image recording region is as large as the print. It is conceivable that even the thermal printer produces a print without the margins. However, there is no known thermal printer in which the margins would be cut appropriately away from the image recording region.
To cut away the margins, it is preferable to use a front margin cutter, rear margin cutter and slitter. JP-B 2833185 and JP-A 08-011087 disclose a slitter including upper rotary blades and lower rotary blades, and in which the upper rotary blades is shiftable relative to the lower rotary blades between a slitting position and retracted position.
The slitter according to the prior documents has a shifting mechanism of a pivotally movable type, which shifts the upper rotary blades from the slitting position to the retracted position. There is a shortcoming in that a considerable space is required for swinging the upper rotary blades inside the printer. This space causes the cutting device to have a great thickness, and inconsistent to reducing the size of the cutting device or printer. Also, a problem lies in that ejector rollers must be disposed additionally.
In view of the foregoing problems, an object of the present invention is to provide a printer capable of cutting margins, in which a space for containing a blade shifting mechanism is saved, and of which a size is relatively small.
In order to achieve the above and other objects and advantages of this invention, a printer is usable with a recording material extending two-dimensionally in a main scan direction and a sub scan direction substantially perpendicular to the main scan direction. At least one cutter removes at least one of front and rear margins from the recording material by cutting the recording material along a line extending in the main scan direction. A slitter removes at least one of first and second side margins from the recording material by slitting the recording material along a line extending in the sub scan direction. A slitter shifter shifts the slitter in the main scan direction between a slitting position and a home position, the slitter being set at the at least one side margin when in the slitting position, and being away from the recording material when in the home position. An externally operable mode selector selectively sets a marginless mode and a margin mode. A controller causes the slitter shifter to shift the slitter to the slitting position when the marginless mode is set, and actuates the cutter and the slitter, the controller causing the slitter shifter to shift the slitter to the home position when the margin mode is set, and for disabling the cutter and the slitter.
Furthermore, a feeder feeds the recording material in the sub scan direction. The cutter is actuated while the feeder is stopped. The slitter is stationary in relation to the sub scan direction, and slits the recording material by actuation of the feeder.
The slitter includes first and second blades arranged in the main scan direction, and have cutting edges directed in the sub scan direction. Third and fourth blades are disposed opposite to respectively the first and second blades with reference to a thickness direction of the recording material, slid by the slitter shifter between the slitting position and the home position, wherein cutting edges of the third and fourth blades, when in the slitting position, are opposed to respectively the cutting edges of the first and second blades in the main scan direction, for slitting the recording material.
The at least one cutter comprises a front margin cutter for cutting away the front margin from the recording material. A rear margin cutter cuts away the rear margin from the recording material.
According to a preferred embodiment, the slitter is disposed downstream from the front and rear margin cutters in the sub scan direction. The slitter and the rear margin cutter are actuated after the front margin cutter is actuated.
Furthermore, an edge sensor is disposed close to the rear margin cutter, for detecting an edge of the rear margin in the recording material. The controller, while the slitter cuts away the at least one side margin, stops the feeder in response to a signal from the edge sensor, actuates the rear margin cutter while the feeder is stopped, and then actuates the feeder to cause the slitter to cut away remainder of the at least one side margin.
The cutter includes a stationary cutter blade having a cutting edge extending in the main scan direction. A movable cutter blade has a cutting edge opposed to the cutting edge of the stationary cutter blade in the sub scan direction. A blade moving mechanism moves the movable cutter blade along the stationary cutter blade.
The movable cutter blade is circular. Furthermore, a blade holder is secured to the blade moving mechanism, for supporting the movable cutter blade in a rotatable manner.
According to a preferred embodiment, a failure detector detects failure in a cutter operation of the cutter. The controller, when failure in the cutter operation is detected, causes the slitter shifter to keep the slitter in the home position.
The blade moving mechanism moves the movable cutter blade from a first position to a second position in the main scan direction, and then moves the movable cutter blade from the second position back to the first position. Furthermore, a position detector detects that the movable cutter blade is in the first position. The failure detector includes a timer for measuring moving time elapsed after the movable cutter blade is initially in the first position and before the movable cutter blade moves back to the first position after movement. The controller compares the moving time with reference time, and detects occurrence of failure if the moving time is longer than the reference time, the reference time being predetermined according to the cutter operation of the movable cutter blade with normality.
The at least one cutter comprises a front margin cutter for cutting away the front margin from the recording material. A rear margin cutter cuts away the rear margin from the recording material. The timer is associated with the movable cutter blade in the front margin cutter.
The blade moving mechanism moves the movable cutter blade from a first position to a second position in the main scan direction, and then moves the movable cutter blade from the second position back to the first position. The failure detector includes an overload detector for monitoring load applied to the movable cutter blade while the blade moving mechanism moves the movable cutter blade toward the second position, and for detecting overload if the load is higher than reference load, the reference load being predetermined according to the cutter operation of the movable cutter blade with normality for the recording material. When the overload is detected, the controller causes the blade moving mechanism to move the movable cutter blade to the first position.
The blade moving mechanism includes a cutter motor, controlled by the controller, for rotating forwards and then backwards, to move the movable cutter blade. The overload detector monitors load to the cutter motor while the cutter motor rotates forwards. When the overload is detected, the controller forcibly causes the cutter motor to rotate backwards.
According to a preferred embodiment, the feeder includes at least first and second feed rollers for nipping the recording material and for feeding thereof in the sub scan direction. First and second support shafts extend in the main scan direction, for supporting and rotating the first and second feed rollers. The first and second blades are circular and secured to the first support shaft, and the third and fourth blades are circular and secured to the second support shaft.
Furthermore, a shock absorber absorbs shock received by the third and fourth blades from the first and second blades when the slitter shifter causes the third and fourth blades to contact the first and second blades in the slitting position.
The third and fourth blades are disposed above the first and second blades.
The slitter shifter includes a shifter motor. First and second support mechanisms support respectively the third and fourth blades on the second support shaft in a slidable manner. A cam mechanism is shifted by the shifter motor between first and second shifted positions, for driving the first and second support mechanisms, wherein the cam mechanism, when in the first shifted position, shifts the third and fourth blades to the slitting position, and when in the second shifted position, shifts the third and fourth blades to the home position.
Each of the first and second support mechanisms includes a support sleeve, secured to the second support shaft in a slidable manner, and having the third or fourth blade secured thereto. A sliding sleeve is secured to the second support shaft in a slidable manner between an axial end of the second support shaft and the support sleeve. The shock absorber is a coil spring, disposed between the support sleeve and the sliding sleeve, for receiving insertion of the second support shaft.
Each of the first and second support mechanisms further includes a holder plate, disposed between the axial end of the second support shaft and the sliding sleeve, for receiving insertion of the second support shaft in a rotatable manner, the holder plate being slidable with reference to the second support shaft, for preventing the support sleeve and the sliding sleeve from dropping away from the second support shaft. A support bracket is secured to the holder plate, and extending substantially along the second support shaft. A cam follower pin projects from the support bracket, and is driven by the cam mechanism. A rectilinear guiding mechanism guides movement of the cam follower pin in the main scan direction.